The DM36x processor includes a hardware resizer module to perform image-scaling operations and color space conversion. There are three different ways you can use the hardware resizer with GStreamer:

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# '''Chain ipipe with v4l2src element:''' The v4l2src element provides the property ''chain-ipipe'', that indicates if the element must chain (use) the ipipe preview and resizer hardware modules. When chained, you capture from the image sensor or YUV decoder with the ipipe preview and resizer modules configured for continuous mode of operation. This means the previewer and resizer are included in the video frame data path, processing each captured frame to do image tuning and resizing. Due to hardware limitations, the image scaling is only available for use with video frames from a YUV decoder. If you use a raw image sensor the imaging scaling module only allows you change the color space. The following is a pipeline that resizes the 640x480 input video frames to a different resolution. You simply specify the capabilities filter setting to the desired width and height.

# '''Use dmairesizer element:''' The dmairesizer element configures the DM36x hardware resizer and use it to scale each video input frame to the desired resolution. In this case, the DM36x resizer operates in single-shot mode, meaning the ARM processor needs to pass each buffer containing a video frame to the resizer. If you use this mode with v4l2src element, you must set the property ''chain-ipipe'' to false since the resizer can't be used simultaieosuly in continus and in single-shot modes. The following is an example pipeline using dmairesizer.

The DM36x processor includes a hardware resizer module to perform image-scaling operations and color space conversion. There are three different ways you can use the hardware resizer with GStreamer:

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# '''Chain ipipe with v4l2src element:''' The v4l2src element provides the property ''chain-ipipe'', that indicates if the element must chain (use) the ipipe preview and resizer hardware modules. When chained, you capture from the image sensor or YUV decoder with the ipipe preview and resizer modules configured for continuous mode of operation. This means the previewer and resizer are included in the video frame data path, processing each captured frame to do image tuning and resizing. Due to hardware limitations, the image scaling is only available for use with video frames from a YUV decoder. If you use a raw image sensor the imaging scaling module only allows you change the color space. The following is a pipeline that resizes the 640x480 input video frames to a different resolution. You simply specify the capabilities filter setting to the desired width and height.

# '''Use dmairesizer element:''' The dmairesizer element configures the DM36x hardware resizer and use it to scale each video input frame to the desired resolution. In this case, the DM36x resizer operates in single-shot mode, meaning the ARM processor needs to pass each buffer containing a video frame to the resizer. If you use this mode with v4l2src element, you must set the property ''chain-ipipe'' to false since the resizer can't be used simultaieosuly in continus and in single-shot modes. The following is an example pipeline using dmairesizer.

Video playback

The previewer and resizer for video capture must be initialized by the user. You can do that in two ways:

1. Compile and install the ipiped application located in the File System Configuration->Select target's file system software section of the configuration screen (make config). This application allows to get control over some video capturing properties (for more information see Auto exposure and auto white balance library). You can initialized the previewer and resizer by running the following command:

ipipe-client run-config-script dm365_mt9p031_config

or you can run this command instead:

ipipe-client set-previewer-mode cont

NOTE: The initialization must be done before any video capture session.

2. The V4L2 source element (v4l2src) as a build in property called chain-ipipe which automatically initializes the previewer when it is set (by default it is set to true).

NOTE: when using one of the methods described above the other one must not be used since this can create a conflict when the code tries to re-initialize the previewer.

Video Resizing

The DM36x processor includes a hardware resizer module to perform image-scaling operations and color space conversion. There are three different ways you can use the hardware resizer with GStreamer:

Chain ipipe with v4l2src element: The v4l2src element provides the property chain-ipipe, that indicates if the element must chain (use) the ipipe preview and resizer hardware modules. When chained, you capture from the image sensor or YUV decoder with the ipipe preview and resizer modules configured for continuous mode of operation. This means the previewer and resizer are included in the video frame data path, processing each captured frame to do image tuning and resizing. Due to hardware limitations, the image scaling is only available for use with video frames from a YUV decoder. If you use a raw image sensor the imaging scaling module only allows you change the color space. The following is a pipeline that resizes the 640x480 input video frames to a different resolution. You simply specify the capabilities filter setting to the desired width and height.

Use dmairesizer element: The dmairesizer element configures the DM36x hardware resizer and use it to scale each video input frame to the desired resolution. In this case, the DM36x resizer operates in single-shot mode, meaning the ARM processor needs to pass each buffer containing a video frame to the resizer. If you use this mode with v4l2src element, you must set the property chain-ipipe to false since the resizer can't be used simultaieosuly in continus and in single-shot modes. The following is an example pipeline using dmairesizer.